Hydraulic transmission control



1950 A. L. J-OI-IINSON EI'AL 2,527,820

HYDRAULIC TRANSMISSION CONTROL Filed Jan. 19, 1945 7 Sheets-Sheet, 1

Fiel

Albefl: L.Johnson nd SelmerAKrafc Gttornegs Zmnentors Oct. 31, 1950 A.L. JOHNSON ET AL HYDRAULIC TRANSMISSION CONTROL 7 Sheets-Sheet 2 FiledJan. 19, 1945 ONH L'Ittonlegs Get. 31, 1950 A. L. JOHNSON ET AL2,527,820

7 HYDRAULIC TRANSMISSION CONTROL Filed Jan. 19, 1945 I '7 Sheets-Sheet 4FieA' lnventors Albert Ldohnson d SelmerAKrafc Gttomegs Oct. 31, 1950 A.L. JOHNSON ETAL 7,

HYDRAULIC TRANsmIssI'oN CONTROL Fi led Jan. 19, 1945 7 Sheets-Sheet 53nnentor5 Albert L.Johnson d SelmerAKrafi (Ittorneg:

Oct. 31, 1950 A. 1.. JOHNSON ETAL- 2,527,820

- HYDRAULIC TRANSMISSION cou'raol.

Filed Jan. 19, 1945 '7 Sheets-Sheet 6 3nnentors '76 8'7 Alberc L.Johnsond SelmerAKrafc attotnegs OCLBI, 1950 JOHN SON ETAL 2,527,820

HYDRAULIC TRANSMISSION CONTROL Filed Jan. 19, 1945 '7 Sheets-Sheet 7FielB REVERSE NEUTRAL FIRST SECON THIRD FOURTH SI TH 31'3 SEVENTH 31Gttoruegs Patented Oct. 31, 1950 HYDRAULIC TRANSMISSION CONTROL Albertll. Johnson, St. l'raul, Minn, and Selmer A. Kraft, Milwaukee, Wis.,assignors to Johnson Power-n Transmission Corporation, a corporation ofMinnesota Application January 19, 1945, Serial N 0. 573,476

6 Claims. 1

Our invention relates to an improvement in hydraulic transmissioncontrol, wherein it is desired to provide an apparatus capable ofcontrolling the operation of a transmission or the like.

The present application is in part a continuation of our applicationSerial No. 486,809, filed May 13, 1943, now Patent No. 2,415,885. Thepresent application is directed to the control mechanism.

In a co-pend-ing application fried in the name of Albert L. Johnson,Serial No. 384,792, now Patent No. 2,348,980, a planetary typetransmission was described embodying friction type clutches to holdvarious elements of the transmission from relative rotation. While thispreviously described transmission was entirely successful in itsoperation, certa-inadvantages were felt to exist in a hydraulic clutcharrangement capable of taking the place of the friction clutches.

It is the object of the present invention to provide a hydraulic controlfor a transmission or the like capable of holding various elements ofthe transmission from relative rotation. In some instances it is desiredto hold two rotatable elements together to cause rotation of theseelements in unison. sired to hold certain rotative parts stationary. Ourhydraulic clutch mechanism is capable of accomplishing these results ina simple and effective manner.

A feature of the present invention lies in the provision of a clutchembodying a fixed casing, a rotative member rotatably supported in saidcasing, and a second relatively rotatable element independentlyrotatable within the first named rotatable element. Means are providedfor looking the two relatively rotatable members together for operationin unison and means are also provided for locking one of the rotatablemembers in stationary position. This double :action of the clutch devicerenders the same capable of accomplishing a multiplicity of .d-iiierentresults.

A feature of the present invention lies in the provision of a clutchdevice comprising a rotatable element within a casing and .in providingvane means in the rotatable element engageable with the casing. Therotatable element is held stationary when so desired by projection ofthe vanes into engagement with a cam-shaped pocket in the casing. Whenpreferred, however, the vanes maybe retracted into the rotatable memberto rotate therewith without creating undue friction or back pressure;and without the necessity .of circulating oil.

In other instances it is de- A further feature of the present invention.lies in the provision of an inner rotatable member positioned withinanlouter rotatable element in the provision of .a cam-shaped outersurface on the inner rotatable member'which is engageable with the vanemeans on the outer rotatable member. As a result when the vane meansproject inwardly from the outer rotatable member they may act to preventrelative rotation between the two relatively rotatable elements.However, when the vane means are in outwardly projecting position thesame vane means may act to hold the outer rotatable member stationary inits casing.

A further feature of the present invention lies in the provision oflocking means capable of holding the vane means in intermediateposittion retracted into the outer rotatable element. Thus the tworotatable members .mayrotaterelative to each other and relative to thecasing with.- out undue friction .or circulation of hydraulic liquid.

A further feature of the present invention-lies in the provision of anautomatic control capable of actuating the vane means carried by theouter rotatable member. This control is operable .in

response .to the volume of liquid pumped by .a

turn reduces the volume of liquid pumped to the control. The speed ratiomay be changed under various conditions. First, the ratio may change byvarying the speed of the driving motor.

Second, upon acceleration of the motor the speed ratio may vary.

Third, the idling adjustment, or dash adjustment has a bearing on thespeed ratio and the time required to change from one speed ratio to thenext. "In the fourth place, the

control may be set to limit change of speedratio.

In the ffifth place, manual operation of the control may take place whendesired. Finallyywhen so desired, the automatic control may function tovary the speed ratio through an entire range of speeds from a low speedto a high speed ratio lies in the provision of a clutch in the form of avane pump, in which a rotor supporting slidable vanes is mounted forcooperation with a camshaped surface. Means are provided wherebypressure on opposite sides of each vane is equalized during the slidingmovement of the vane, or during projection or retraction of each vane.

These and other objects and novel features of our invention will be moreclearly and full set forth in the following specification and claims.

In the drawings forming a part of our specification:

Figure 1 is a side elevational view, partly in section, showing ourtransmission and controlling unit therefor.

Figure 2 is a transverse section taken substantially on the line 22 ofFigures 1 and 3.

Figure 3 is a longitudinal section through onehalf of the transmissionon substantially the line line 33 of Figures 1 and 2.

Figure 4 is a vertical section taken substantially on the line 4-4 ofFigure 1.

' Figure 5 is a sectional view taken on substantially the line 55 ofFigure 4.

Figure 6 is a section taken substantially on the line 66 of Figure 4.

Figure '7 is a sectional view taken substantially on the line 'l-! ofFigure 4.

*Figure 8 is a sectional view taken on the line 38 of Figure 4.

Figure 9 is a sectional view, the position of the section being shown bythe line 99 of Figure 4. Figure 10 is a diagrammatic view showing afvalve cylinder in diagrammtic form Figure '11 is a sectional viewthrough the trans- 'n1 i ssion, the position of the section beingindicated'by the line I I l l of Figure 3.

Figure'12 is a sectional View through a clutch unit', the position ofthe section being indicated by the line I2l 2 of Figure 3.

Figure 13 is a diagrammatic view of the controlvalve.

t Figure 14 is a diagrammatic view showing the transmission connectedwith the engine and illustrating the interconnection between a control.member of Y the transmission and the engine throttle.

"The transmission is best illustrated in Figures land 3 of the drawings,Figure 1 illustrating the outer appearance thereof, while Figure 3 is atransverse section through slightly more than one-half of the same. Thetransmission gears are enclosed by an inner gear housing positionedwithin a tapered housing or enclosure H! having an attachment flange Hthereon, by means of .which the housing may be secured to the drive.unit which may comprise an internal combustion .engine or the like. Asviewed from the top, as in Figure 3, the cone-shaped portion ill of thecasing bulges outwardly to some extent because of the operating valveswhich are positioned on 0pposed sides of the transmission housing. Theflange is secured to the power unit by any suit- ;able means such as capscrews 12.

- The following description involves an epicyclic gear transmissionsystem, a clutch system for controlling the rotation of various elementsthereof, and a control system for hydraulically con.- trolling theclutch system. For the purpose of clarity, these systems will bedescribed in succession.

" The transmission system 5 With reference now to Figure 3 of thedrawings, the engine drive shaft, not illustrated in the drawings, ispreferably equipped with an end flange 9, or similar attachment (seeFigure l), to which the hub flange [3 of the gear housing id isattached, Thus, upon rotation of the engine crank shaft, the gearhousing 14 is rotated through the hub 13. The driven shaft I5 ispreferably coaxial with the drive shaft connected to the hub 13 andcoaxial with the gear housing M. Sleeves I 6, I7, and I9 encircle thedriven shaft [5, extending various lengths longitudinally of the same,as will be later more fully described in detail. The sleeve 16 freelyencircles the shaft 15 and may rotate with respect thereto. The sleevell encloses a portion of the sleeve I 8, while the sleeve 19 encloses aportion of the sleeve H.

The gear housing [4 is formed of two portions, one of which includes adisk member 23 extending radially outwardly from the hub l3 and having ahollow cylindrical flange 21 projecting laterally therefrom near theouter extremity thereof. A ring gear 22 is secured to the outerperiphery of the disk 20 so that the housing It may be rotated by astarting motor, when desired, for starting the engine. A second portionof the housing 34 includes a hub 23 supported by a bearing on the endwall of the housing 10 which will be later described, and supports abearing 25 encircling the sleeve IS. A disk 25 extends outwardly fromthis hub 23 for supporting a cylindrical shell 26 of smaller diameterthan the cylindrical flange 2!. A ring-shaped flange 27 is provided onthe extremity of the cylindrical shell 2% and this flange 21 is securedto the cylindrical flange 2! by cap screws 29 or other suitable means.Thus a gear housing is provided, one end of which is secured to thedrive shaft for rotation therewith, and the other end of which issupported by the stationary housing Ill. The disks 2G and 25 form theends of the housing l4, while the connected cylindrical shells 2! and 26form a gear enclosure.

A sun gear 3!! is provided on the driven shaft 15, being splined theretoat 3! and being concentric with the drive shaft. The sun gear 33 iscontinuously meshed with the gear teeth 32 of the double pinion 33. Inactual construction a plurality of such double pinions are supported inan gularly spaced relation about the sun gear 30, as better illustratedin the above mentioned copending application. For the purpose ofillustration, however, it is necessary to show but one of these doublepinions in order to understand the operation of the present device. Thedouble pinion 33 forms the planet gear means of one epicyclic gearsystem.

The double pinion 33 is supported by a bearing 3 encircling a stub shaft35. The stub shaft 35 is supported at one end by a disk-shaped support33, which in turn is supported by a bearing 31 encircling a portion ofthe hub 13 of the gear casing M. A bearing 39 is provided between thedisk-shaped support 36 and the sun gear 30 mounted on the driven shaft15. Thus the support 36 is freely rotatable both with respect to thedrive shaft and with respect to the driven shaft. The disk-shapedsupport 36 is peripherally keyed to a rotor 49 forming the rotativeelement of a clutch R. The construction of this clutch will be morefully described.

The teeth 4| of the double pinion 33 are meshed with a sun gear 42rotatable with the sleeve !5. The sleeve I6 is supported rotatably uponthe shaft l5 and a bearing 43 therebetween prevents excessive frictionand wear between the shaft l5 a d t e l and between the sun gears 30 and-42, caused by end thrust of the sleeve it due to helical constructionof the sun gears. The teeth a! of the double pinion also engage aninternal ring gear d5 upon a rotatable sleeve 45. The sleeve s5 issupported by a central disk d6 mounted upon a bearing 3'? engaging acylindrical flange d9 on a disk 50. The disk 50 extends parallel to thedisk 36 and in spaced relation thereto, and forms a bearing for one endof the stub shaft 35. However, intermediate angularly spaced doublepinions 33, and inangular relation thereto, the disks 36 and 55 arebolted together to rotate in unison and to act as a single unitarysupport.

From the foregoing description it will be noted that we have provided aplanetary or epicyclic gear system including sun gears 3i} and 2, adouble pinion 83- engaging 'both of these sun gears, and a ring gear asengaging the teeth 46 of the double pinion 33. The sun gears 30 and 42are of different diameter, the sun gear 35 being of greater diameterthan the sun gear 42, and the pinion formed by the teeth 32 being ofsmaller diameter than the pinion formed by teeth 4!. The disks 35 and 50supporting the stub shaft 35 form a planetary gear carrier for theplanet gears 3 connecting the sun gears 35 and 32 to the ring gear 46,The ring gear, the sun gears 35 and 42, and the planetary gears 33 areall supported for relative rotation and likewise the planet gear carriercomprising disks 35 and '58 .may revolve independently of these gears.

The disk 5!! assists in supporting the sleeve if? by means of a bearing5i so that the planet gear carrier and the sleeve may rotate freelyabout their respective axes. The disk 35, supporting the sleeve 35bearing the ring gear 451, could likewise be supported by some otherelement, but for the sake of convenience the bearing .13 is providedseparating this disk 45 from .a cylindrical flange :29 on the disk 50.

A second epicyclic gear system is likewise provided within the gearcasing it. This second gear system is connected to the first systemthrough the ring gears of the respective systems, the sleeve 65 beingprovided with a second internal ring gear 52 at the extremity thereofopposite the internal ring gear 34. The two ring gears 44 .and .52 are 1of different diameters, the gear 52 .being shown larger in diameter thanthe gear 44.

A sun gear 53 is mounted upon the end of the sleeve i i and is rotatablysupported by a bearing 5% interposed between the sleeve- H and the hubof the planet gear carrier disk 55. Thisplanet gear carrier disk in turnsupports a bearing .55 between the disk 5.5 and the hub of the gearcarrier disk 5! The bearing 54 absorbs end thrust of sleeve I! due tohelical formation of the teeth of the sun gear .53.

A second sun gear-5] ismounted upon'the sleeve IS. A thrust bearing 59is interposedbetween the end of the sleeve t9 and the sun gear 53 tohold these elements in proper relation and to absorb end thrust due tohelical formation of the gears. A stub shaft-6i! is secured between theplanet gear carrier disk 55 and the housing disk 25, the disk 55 and thehousing disk 25 being secured together by means, not illustrated in thedrawings, so as to rotate in unison. In other words, .the gear carrierdisk 55 is in'parallelspaced relation to the disk 25 forming the endclosure of the housing I and these elements .are bolted together ,atpoints angularly spaced from the angularly spaced shafts 59 so as torotate. asa audit; The sole purpose of the disk 55 is to form a secondscribed as follows.

support for the stub shaft 55, or for. the angularly spaced stub shafts60, so as to strengthen the construction thereof. A double pinion BI ismounted upon the bearing 62 encircling the stub shaft 58. The doublepinion 6! includes pinion teeth 63 designed to engage the sun gear 53and the pinion teeth 54 designed to engage the sun gear 5'! on thesleeve It. The teeth E53 and 6 1 form pinions of different diameters soas to provide additional speed ratios between the drive shaft and thedriven shaft.

The teeth 66 of the double pinion 6! also engage the internal ring gear52 so as to complete a second epicyclic gear system. The planet gearmeans or double pinion 5| is carried by the stub shaft 50 which revolvesabout the driven shaft 15 at the same speed as the drive shaft, as thegear carrier comprising disks 25 and '55 form part of the housing Mwhich is directly connected to the drive shaft. The sleeves El and I9,as well as the ring gear sleeve :35, are all relatively rotatable. Byholding various of these sleeves stationary and by holding variouscombinations of the sleeves from relative movement, varying speeds willbe transmitted from the drive shaft to the driven shaft l 5.

The clutch R will be described in connection with the transmission, asit is embodied directly within the transmission housing M. This clutch Bmay be constructed as best indicated in Figure 11 of the drawings. Theinternal surface of the flange 2! of the gear casing It is provided withoppositely disposed varcuate surfaces, and with a pair of oppositelydisposed pockets 65. These pockets have a base portion 55 which isconcentric with the casing 16. The ends 68 of the pockets es areinclined or cam-shaped to guide the cooperating vanes inwardly oroutwardly in the manner which Will be hereinafter described. The rotor45 is provided with a series of slots 61 therein which support radiallyprojec'table vanes 59. The vanes 59 are urged outwardly into the pockets55 by means of springs it mounted at the base of the vanes. A passage His connected through the housing disk '20 from each end of each pocket65 to a ring-shaped valve chamber i2 within the hub 53. The valvechamber 12 contains a ring-shaped axially slidable valve 13 which isurged in a position to close the passages H by means of a spring 74. Byapplication of pressure through a pressure port 15, the valve 73 may bemoved sli'deably to the left as viewed in Figure 3 of the drawings,opening the passages H and inter-connecting these various passages. Whenthe passages "'H are inter-connected the rotor 58 may rotate withrespect to the housing it, thereby permitting relative movement betweenthe planet gear carrier 55, 5!! with respect to the casing I l, andaccordingly with respect to the drive shaft. When the valve i3 isclosed, however, the rotor 46 and accordingly the gear carrier 35, 56 islocked with respect to the easing H3.

Upon the application of sufficient pressure, which is transmitted pastthe valve 13 through the passages T5 to the pockets 55, the vanes 69will be held inwardly by pressure, thus permitting free rotation of therotor 45 with respect to the casing or housing M with the radiallyslidable vanes 69 retracted.

The operation of the transmission may be de- When a reverse speed is tobe transmitted to the .drivenshaft 15 while the drive shaft rotates in:a forward direction, the valve 13 is closed so that the rotor "Ml is'-locked with respect to the drive shaft. Simultaneously, a lockingmeans, which will be later described, is set into operation, which willhalt rotation of the sleeve H, thereby stopping rotation of the sun gear53. With the sun gear 53 held stationary, rotation of the drive shaftcauses rotation of both of the gear carriers 35, B and 25, 55 in unisonas the gear carrier 3'5, 53 is locked to the rotor 40. Power is thentransmitted through the double pinion unit 6! to the ring gear 52 whichoperates in unison with the ring gear 44. Thus the rotation of the ringgear 44 is controlled by holding the sun gear 53 stationary, and as thegear carriers supporting the double pinions 33 and SI rotate in unisonwith the drive shaft, a reverse rotation is transmitted from the gear 32to the sun gear 33 on the driven shaft !5.

In further explanation, as the sun gear 53 is held fixed and as the gearcarriers rotate at the same speed, the double pinion unit 6! revolvesabout the sun gear 53, which causes the ring gears 52 and 44 to rotatein set relation thereto. The sun gear 35 on the driven shaft I5 isrevolved in a reverse direction faster than it is carried forward by thetransmission, acting to rotate the driven shaft l5 in a reversedirection at a ratio of 5.24 to 1 with respect to the drive shaft in thetransmission illustrated.

In order to place the transmission in neutral position the valve 13remains closed but the sleeve His released, permitting the sun gear 53to rotate. Because of the closure of the valve 13 the clutch R remainslocked rotating the rotor 49 in unison with the casing l4. Therefore, as

in the case of reverse speed, both planet gear carriers are rotated inunison with the drive shaft.

As there is no restriction on the movement of any of the sun gears inthis position the double pinions 33 and 6! merely idle about theirrespective sun gears, exerting no power upon the driven shaft l5. As aresult no driving power is transmitted to the driven shaft l5, andtherefore the transmission is in neutral.

When it is desired to move the driven shaft 45 forwardly at a low rateof speed, the clutch R remains engaged to lock the rotor 45 to the shaftl5. As a result no driving power is transfrom rotation, thereby holdingthe sun gear 5'! stationary. The double pinion BI is then caused torotate about the sun gear 51. By means of the double ring gear 52, 44movement is transmitted to the double pinion unit 33 which causesrotation of the sun gear 30 on the driven shaft l5. The relativerotation of the gear units 6! and 33 provides a forward rotation of thedriven shaft of 5.77 to 1 with respect to the driving shaft in theparticular transmission illustrated.

When an increased speed of the driven shaft I5 is required, the sleeve19 is released, and the sleeve I6 is held from rotation. The clutch Rremains locked so that both planet gear carriers rotate in unison. Thisaction stops rotation of the sun gear 42, causing the double pinion unit33 to rotate about the sun gear 42, and causing the gear 32 of this unitto rotate the sun gear 30 on the driven shaft l5 at a speed ratio of3.95 to 1 in the transmission illustrated with respect to the driveshaft.

When the next higher speed of the driven shaft is desired, the clutch Ris released, while the sun gear 42 remains stationary. At the same timemeans are provided to lock the sun gear 53 from rotation. This lockingof the sun gears 42 and 53 from rotation results in a rotation of thering gear 44, 52 and of the double gear unit 33 which will drive thedriven shaft l5 at a speed ratio of 2.47 to 1 with respect to the driveshaft in the particular transmission illustrated.

When the next higher speed of the driven shaft is desired, the sun gears53 and 4'2 remain clutched together for rotation in unison and at thesame time the sun gear 51 is braked and thus held stationary. In thisposition the sun gears 42 and 53 are not held stationary, but are merelyclutched against relative rotation while the sun gear 51 is locked instationary position. The gear unit 6! is forced to revolve about the sungear 51 and to provide a definite rate of rotation of the ring gear unit44, 52 and of the sun gears 42 and 53. This action produces a rate ofrotation of the driven gear 30 on the driven shaft l5 which is 1.71 to 1with respect to the drive shaft in the particular transmissionillustrated.

In the next higher speed of the driven shaft !5, this driven shaft I5 isrotated at the same speed as the drive shaft. This result isaccomplished by maintaining the sun gears 33, 42 and 53 locked forrotation in unison and in holding these sun gears locked from rotationwith respect to the driven shaft. This action results in holding the sungears 30 and 42 from relative rotation, and as both of these gearsareengaged by the double pinion unit 33, all of the gears are locked fromrelative rotation and the entire transmission rotates in unison.

When an over-drive speed of the driven shaft i5 is desired the sun gear42 remains clutched to the driven shaft and simultaneously the sun gear51 is held from rotation. The double pinion unit 3! is then forced torotate about the fixed sun gear 51, rotating the ring gear unit 44, 52to rotate the double pinion unit 33. As the sun gears 30 and 42 areclutched together against relative rotation the planet gear unit 33 cannot rotate, therefore preventing relative rotation of the ring gear 44with respect to the planet gear unit 33. Thus one epicyclic gear systemis locked from rotation and as the sun gear of the other epicyclic gearsystem is held fixed, the drive shaft l5 must rotate with the ring gear44, 52 at a higher rate of speed than the drive shaft. The driven shaftis thus rotated at the ratio of 1 to 1.38 with respect to the driveshaft in the transmission illustrated.

When a higher rate of over-drive is required the sun gear 42 remainslocked from rotation with respect to the driven shaft l5, thus holdingthe corresponding epicyclic gear train locked from relative rotation andcausing the driven shaft to remain locked to the ring gear unit 44, 52.However, in this speed ratio the sun gear 51 is released and the sungear 53 is held from rotation, thus causing the double gear unit 55 torotate around the larger sun gear 53 and thereby transmitting increasedspeed of rotation to the ring gear unit 44, 52. In the transmissionillustrated the speed ratio is 1 to 1.55 with respect to the drive shaftwhen thus controlled.

The clutch and brake system From the foregoing description of thetransmission operation, it will be obvious that various locking meansare required for the sun gears 42, 53, and 51. In order to controlrotation of these sun gears they are independently mounted on theirrespective sleeves l6, l1, and I3 and for convenience these respectivesleeves are held from rotation or locked to rotate in unison asrequired.

The clutch holding the two planet gear carriers locked for rotation inunison has already been described as clutch R. A brake A is provided forlocking sleeve I9 stationary. A brake Bis provided for locking sleeve I6stationary. A clutch C is provided for locking sleeve I6 to the drivenshaft 55. A brake D is provided for locking sleeve I6 stationary. Aclutch E is provided for holding sleeves I6 and I7 locked together.These five devices are divided into three units; brake A forming oneunit, brake B and clutch C forming a second unit, and brake D and clutchE forming a third unit. The operation of the last two of these units,and the construction thereof is virtually identical.

Actuation of these clutches and brakes holds certain of the sleevesstationary, or locked together for operation in unison. The followingtable lists a number of speed ratios the transmission illustrated mayattain, together with the clutches and brakes which must be engaged toproduce these ratios.

Attached to the end of the frusto-conical housing l8 opposite the endbearing the flange II, we provide a substantially cylindrical casingsection 76. A similar section 77 adjoins the section 78 and a thirdsection 79 adjoins the casing section 77. The section I6 is designed toenclose the bra e A. The section 77 is designed to accommodate a doubleacting clutch and brake, comprising brake D and clutch E. The casingsection 79 is designed to accommodate a second double acting clutch andbrake, comprising brake B and clutch C respectively. An end plate 853closes the section 79 so as to form a complete housing.

A brake A is best illustrated in Figures 3 and 12 of the drawings. Therotor hub 85 is splined to the sleeve I9 to rotate therewith. A ringlikeweb 32 extends outwardly from the hub 8| to support a substantiallycircular rotor 83. The rotor 83 is slotted at angularly spaced points .81 to accommodate vanes 85 which are radially slidable in the slots 84.

The casing section 76 is bored internally to fit closely adjacent theouter periphery of the rotor 83 throughout somewhat less than one-halfthe circumference thereof. A pair of opposed pockets 87 are provided,however, on opposite sides of the rotor into which the vanes 85 mayextend. The pockets 87 are provided with elongated cylindrical segments89 connected to the smaller diameter portions of the internal bore byinclined cam portions 90, which guide the vanes inwardly into the rotoror outwardly therefrom.

The brake A is designed for the express purpose of holding the rotor 83from rotation with respect to the casing section 76. When hydraulicfluid is trapped in the pockets 87, and when the vanes 85 project intothese pockets, the rotor 83 is held from rotation. However, when the oilis allowed to escape from or to flow out of the pockets 37, or when thevanes 85 are held retracted into the rotor, rotation of the rotor 33with respect tothe casing section It is possible.

.3 of the drawings.

In order to hold the vanes retracted to permit free rotation of therotor 83 within the casing section 76, we provide a plunger 91 having apoint 92 thereon designed to engage in a recess in each of the vanes 85.The plunger 9I is urged against its corresponding vane 85 by a spring atwhich is adjustably held in place by a plug 95. Thus as each vane 85engages the inclined end of a pocket 87, and is retracted into the rotor83, it will be engaged by the point 92 of the plunger 9|, unless meansare pro-1 vided for holding the plungers retracted. In other words, inthe absence of any means for holding the plungers 9i retracted, eachplunger will engage its corresponding vane as soon as the vane isretracted by rotation of the rotor with respect to the casing section76, and will lock the vane in retracted position.

In order to hold the plungers 9i from engagement with the vanes weprovide a hydraulic pressure passage 95 through the end wall 97 of thecasing section 76, which communicates through a ring-shaped groove 98with a transverse passage 99 through each vane 85 to the aperture 93 inthe vane. When pressure is exerted through the passages 96 and 99 in amanner which will be later described in detail, :this pressure willretract the plunger 92, thereby'ac'ting to withdraw the point 92 of theplunger from the aperture 93. The vanes are then free to move outwardlyin the slots 84, being moved out wardly by centrifugal force and bysprings I00 between the vanes andthe rotor'8 A hydraulic cushion toreduce shock of engagement is provided by the hollow interior of therotor 83. This chamber within the rotor is always partially filled withair; and sleevedpassages 93 communicate therewith in such a manner thatfluid forwardly of the vanes 85 may be compressed into the air chambers.

In order to segregate the brake mechanism from the transmissionmechanism and to form a support for the transmission elements, theconical portion I t of the housing is provided with an end wall IOIwhich terminates in a hub I52 in spaced relation to the hub 23 of thetransmission casing I i. A bearing I03 separates the hubs 23 and H32 andpermits relative rotation between the transmission housing I4 and theouter housing IE3.

The end wall Q7 of the casing section 76 supports a ball bearing IE4which separates the inner extremity of the wall 97 from the hub I05 ofthe rotor H16 of the combined clutch and brake mechanism E D within thecasing section 77. The hub IE5 is spline connected at I07 to the sleeveI7 and the sun gear 53 mounted thereupon.

The manner in which the housing section" is constructed is bestillustrated in Figures 2 and a hub I I8, spline connected at III to thesleeve I5 bearing the sun gear 42. This cam I09 is supported between thesides IE2 and N3 of the rotor I96 to be spline connected to the sleeveI'I.

The rotor we includes a series of slots II4 for A cam I59 is providedwith I,

..-respect to the casing 11 whenthe vanes are projecting outwardly andto lock the rotor I06 and the internal cam I09 for rotation in unisonwhen these vanes are projecting inwardly.

Each vane H is provided with a slot III! in one surface thereof leadingtoward the outer extremity of the vane. A second slot I is provided inthe opposite side thereof. A plunger I2I is mounted adjacent each sideof each vane H5 in the rotor I06 and positioned with its axissubstantially normal to the plane surface of the adjacent vane II5. Eachplunger I2I is provided with a tip end or point I22 designed to enthetension of each spring I23.

Therefore, it should be noted that the plunger points I22 normallyengage in a slot I20 to lock the vane self-contained within the outerperiphery of the rotor I06, but permit the vanes to slide inwardly.However, upon retraction of the cooperable plungers the points I22thereof are disengaged from the slots I20 to permit the vanes to slideoutwardly. The plungers I2I are retracted by oil under pressure passingthrough transverse passages II8 adjacent the vanes H5.

The grooves II9 permit free outward move- 3 ,ment of the vanes whenoutward pressure is exerted upon the same, and limit inward movementthereof. The cooperable plungers I2I may be retracted by oil pressurepassing through the cooperable passage IIB, allowing the vanes II5 toslide inwardly.

When the vanes I I5 are in their outwardly projecting positionillustrated near the top of Figure 2 of the drawings, these vanes mayextend into the opposed pockets I formed in the casing section 'I'I.Each pocket I25 includes an arcuated section I26 concentric with therotor I66 and terminates in a cam incline I21 at each end thereof so asto guide the vanes H5 inwardly or outward- 1y. Thus when the plunger I2Iin the slots I20 are retracted so that the vanes can move intoengagement with the cam surface I I1 of the casing section II the vanesgradually move outwardly along the cam incline I2! until they reach thearcuated section I26 concentric with the driven shaft and remain on thisarcuated section for a considerable period of time.

Hydraulic liquid in the pockets I25 may bypass the vanes I I5 when thevanes are on the cam inclines I2I of the cam surface III. A pocket orrecess I29 extending a portion of the Width of the vanes II5communicates with the cam inclines I21 and with the control valvetherefor, so that as soon as the vanes I I5 come in communication withthe cam inclines the pressure may equalize on opposite sides of thevanes. We have found that the vanes II5 then have a tendency to snapinwardly, due to pressure on the extremity.

The vanes II5 are therefore not in operation unless they are inengagement with the arcuated surface I26 of the pockets. When thusengaged the hydraulic fluid can not by-pass the vanes and pressure maybe built up in advance of the vanes so as to lock the rotor I06 withrespect to its casing 11. The vanes I I5 are angularly spaced so thattwo opposed vanes are always in position to engage the arcuated surfaceI26 of the opposed pockets I25. When one of the vanes II5 engages thecam incline I21 after traversing the LII entire length of the arcuatesurfaces I26, the next adjacent vane is just leavin the cam incline I 21at the other end of the pocket I25 and therefore is Corning intooperation. This is extremely important as there is no great pressure onany one side of the vanes II5 during their sliding movement because thepressure is equalized on both sides of the vanes during their slidingmovement.

The pocket or passage I29 is in the form of a passageway leading fromeach end of each pocket I25 to its respective control valve which willbe later described. Intermediate the pockets or passages I29 we providean arcuated closed segment I30 between the cam portions I27 of the camsurfaces III of the casing section I! which is longitudinally slottedexcept at its mid-point. When the outer ends of the vanes I I5 are inengagement with the arcuated segment I30, these vanes are fullyretracted into the rotor I06.

In order to cushion the action of the vanes H5 in holding the rotor I06from relative rotation with respect to the casing section II the rotorI'IIB is hollow and is divided into two axially spaced chambersseparated by a central partition wall. Openings I3I through the outerwall of the rotor I06 lead to the interior thereof and the rotor may bepartially filled with hydraulic fluid because of the fact that theopenings I3I into one of the chambers I32 are provided with inwardlyextending sleeves I33. However, the entire chamber I32 can not fill withoil, but contains a certain amount of air which may act as a cushion tothe action of the vanes. In other words, when the vanes II5 are in theposition shown in Figure 2, the hydraulic fluid trapped in the pocketsI25, forwardly of the vanes I I-5 may be partially forced into theinterior of the rotor, compressing the air therein and decreasing shockby permitting the rotor to stop gradually.

For each vane I I5 is provided a passage I28 through the casingconnecting the slot I20 therethrough with the inner end of the vane.Hydraulic fluid under pressure may pass through the passages I26 andthrough the transverse passages IIB, holding the plungers I2I retracted.Hydraulic pressure acting upon the outer ends of the vanes II5 may forcethe same inwardly.

The vanes II5 may also co-act with the cam surface II6 of the cam I09.As has been previously explained the cam I09 is provided with a hub III!which is spline connected to the sleeve I6 encircling the shaft I5. Thecam surface I I6 is provided with opposed arcuate sections I34, but thearcuate portions I34 terminate at the points I35 where the surfaceblends into inclined cam portions I36. Each pair of opposed inclined camportions I36 terminate in a large diameter portion or cam point I31 of adiameter to fit closely within the inner surface I39 of the rotor I06.In other words, the points I31 of the internal cam I09 closely contactthe inner surface of the rotor I66, while opposite halves of the camsurface II6 are formed by the arcuated portions I34. Thus if the vanesII5 are urged inwardly against the cam surface II 6, they will moveinwardly the greatest amount throughout contact with the arcuatedportions I34 of the surface. The vanes II5 will then be urged outwardlyby the inclined cam portions I36 until they are fully retracted into therotor I06. The vanes will then travel down the next inclined cam portionI36 until they engage the next adjacent arcuated surface I34. The vanesI I5 thus reciprocate twice during each rotation of the internal camI09.

As best illustrated in Figure 3 of the drawings,

a, ring-shaped slot or recess I40 is formed in the cam rotor I59 toreceive a ring-shaped axially slidable valve II. The valve MI isnormally urged in one direction by a spring I42. Passages its leadthrough the wall ofthe cam adjacent each inclined portion I36 thereof sothat while the vanes I I are in engagement with these inclined portionsI36, hydraulic fluid may by-pass the blades. Furthermore, while thevalve meme ber MI is in the position illustrated in Figure 3 of thedrawings, the hydraulic fluid can freely flow through the grooves. Ifrom one. opening or passageway I33 to. the next. The wall of the camIE5 is solid adjacent the arcuate surfaces I34 and also at the oppositepoints I31 of the cam, the openings I453 being positioned between theextreme points of the cam and the arcuated surfaces IS I thereof.

When the vanes II5 are inwardly projecting against the cam surface IIBthe hydraulic fluid pumped by the vanes can freely flow from one passageI43 to the next adjacent passage when the valve I lI is open. However,when the valve I ZI is moved to the right from the position illustratedin Figure 3 so as to close the passage between the passages I43, thefluid within the pockets I4 formed between the rotor I58 and theinternal cam I59- on opposite sides of the points I37 of the cam, willbe trapped therein and a relative rotation between the rotor I66 and thecam I59 can not take place. Therefore when thus engaged thesetwoelements must rotate in unison.

In order to cushion the shock of engagement between the rotor H36 andthe cam I09, we provide openings I45 through the inner wall of the rotorI06 leading into chambers I45, occupying one-half of the hollow volumeof the rotor and spaced axially from the chamber I32 into which theopenings I3I extend. These openings I45 are each provided with anoutwardly extending sleeve I I'I which prevents the entire chamber fromfilling up with hydraulic liquid and therefore provides an air cushionwhich may compress to some extent under pressure so as to cushion theShock of engagement between the elements I06 and I59.

The brake B and clutch C, illustrated in Figure 3, are virtuallyidentical with the brake D and clutch E which have been described, withthe exception of the hub structure. The internal cam I 39 of the clutchC is identical to the internal cam me with the exception that the hubI58 thereof is of somewhat smaller diameter than the hub H0 and isspline connected at I5I directly to the driven shaft I5. A rotor I52,substantially identical to the rotor I05, is provided with a hub I55,spline connected at I54 to the sleeve I5. Externally of the hub I53 isprovided a bearing I55 to separate the hub I53 from the end wall I55 ofthe casing section TI. This casing end wall I55 extends between thesideplate II2 of the rotor I55 and the side .plate I51 of the rotor I52.The side wall I5I of the rotor I52 extends along one end of the cam I49.The other side plate I59 of the rotor I52 extends along the oppositeside of the cam I49, thus enclosing the cam I49 between the rotor platesI57 and I59. The side plate I59 is supported by a bearing I60 encirclingthe driven shaft I5.

A ring-shaped slot IGI is provided in the cam I49 to accommodate theslidable Valve I62 which is normally urged into open position by. aspring I63. When urged. in: the opposite direction to compressthespringI63, the valve 11525 is in position to close the openings I543, whichare identical with the openings I43 and accomplish the same purpose.

The vanes I55 mounted in the rotor I52 are identical with the vanes,H5111 the rotor H35, and the casin section I9. is provided with aninternal cam surface I55, identical with the internal cam face of thecasing section TI, illustrated in Figure 2 of the drawings. PassagesI51, identical with the pockets or passages [29, relieve pressure on thevanes I55 when the vanes are engaging a portion of the cam surface I55,which would tend to. move the vanes longitudinally or permit suchlongitudinal movement.

In other words, a sectional view of the brake B and clutch C containedwithin the casing section 719 would be identical with the section shownin Figure 2, except for the fact that the cam I49 is keyed to the shaftI5, rather than to the sleeve I5. The method of operationandconstruction of the brake B and clutch C. is otherwise identical withthat of brake D and clutch E.

The driven shaft I5 may operate any suitable device, but it mostfrequently is connected to a universal joint, such as I55. In suchinstance, the end of the driven shaft I5 may be tapered, as at Ilii forconnection with a portion ill of the universal joint, and bearing meansI12 may be provided between the hub M3" on the end of the closure plateand the casing section IQ for this universal joint portion I'I-I.

The control system The clutch and brake construction used in the haltingof relative movement between the various sleeves controlling the sungears of our transmission have been described. In order to control thetransmission automatically, 9, control means is provided which willselectively engage the various clutch and brake elements and which willtherefore permit successive relative speeds between the drive shaft andthe driven shaft to be built up. This control means, for controlling theclutches and brakes which have been described, will now be described indetail. Similar control units are provided onopposite sides of thehousing Iii; but in the interests of simplicity, but one control isillustrated in detail.

The hub 23 of the transmission housing I4 is provided with worm gearteeth II4which operate a gear H5 on a shaft I76 extending transverselythrough the transmission housing It. On each end of the shaft I75, weprovide a pump I'II. enclosed within an added casing portion I79 of thehousing I5. As best illustrated in Figure 5 of the drawings, the pumpI'I'I is provided with an inlet passage I85, which extends into theinterior of the transmission casing If! to obtain oil from this casinginterior. the oil thus collected through an outlet passage ISI into apressure chamber I82 which may be of any desired shape, but which, inthe construction illustrated, encircles a portion of the transmissioncasing It as best illustrated in Figure 4 of the drawings. As the upperportion of the pressure chamber I82 is preferably filled with air, anoil pressure is thus built up in the chamber for the purpose which willbe hereinafter more clearly set forth.

When sufficient pressure is built up within the pressure chamber I82 thevalve I83 opens automatically to allow oil to escape. is supported in anoutlet port. I84 and is urged by a spring I85 in position'to close. theport I84.

Obviously the valve. I832 will: open under pressure The pump I'I'Ipumps- The valve I83,

to permit oil to flow into the chamber I86. The amount of pressure whichmust be built up before the valve I83 will open may be regulated by thepressure adjustment nut I87, which adjusts the tension of the springI85. The valve I63 is inserted through a threaded port I89, normallyclosed by a cap I99 bearing the adjustment nut I87.

A butterfly valve I9I permits a metered amount of liquid to by-pass intothe reservoir I92 formed within the transmission casing I9. Thus atidling speeds the pressure built up by the pumps I77 may be permitted toescape past the valve I9I. An arm I93 is connected to the shaft of thebutterfly valve I9I so that the setting of this valve may be adjustedand a connection to this arm I93 may be made to any convenient locationso as to control the engagement timing of the control. Naturally themore oil which is allowed to escape past the butterfly valve I91, thelonger will be the time required to build up an adequate volume ofliquid to operate the control.

The volume flow chamber I86 is connected by a passage I94 to aring-shaped chamber I95 encircling the hollow shaft I96 of a rotor I97.Openings I99 through the hollow shaft I96 provide constant communicationbetween the interior passage 299 of the shaft I99 and the passage I95 sothat the volume flow chamber I96 may always be in communication with theinterior of the rotor I97. The rotor I97 is constructed as bestillustrated in Figures 4 and 9 of the drawings, the hollow passage 299of the shaft I96 communicating with a radially extending passage 29I inthe rotor, extending to the outer periphery thereof. The rotor I97includes a hollow cylindrical shell 292 having openings 293 and 294therethrough on opposite sides of the passage 29I. Thus it is obviousthat oil from the volume flow chamber I86 may flow through the interiorshaft passage 299 and the passage 29I and into the hollow cylindricalcasing shell 28S forming a part of the transmission housing I9, as bestillustrated in Figure 4.

A sleeve 296 encircles the shell 292 and is provided with a radiallyextending partition wall 297 which is secured to the casing shell 295 at299 by any suitable means, such as by extending the wall 297 into agroove in the shell 295. Apertures M9 and 2 are provided in the sleeve296 on opposite sides of the partition wall 297. A projection 2I2 isprovided on the lower end of the partition wall 297, which extends inthe path of the sides of the passage 29I and which therefore limitsrotation of the rotor I97. In other words, the passage 29I may bepositioned as shown, in communication with the area on both sides of thepartition wall 297. However, by rotating the rotor I97 a few degrees ineither direction, the passage 29I may communicate solely with the spaceto one side or the other of the partition wall 297, thus deliverin oileither exclusively through the aperture 2I9 or exclusively through theaperture 2| I.

The shell 292 of the rotor I97 is connected to the shaft I96 by means ofspaced spider arms 2 I3. A disk 2I4 is positioned within the housingshell 295 to be interposed between the rotor I97 and the body of thecrank case which forms a shoulder 2I5 against which the disk 2I4rotates. A hub 2 I6 on the disk 2I4 is internally bored with twoportions of diiferent diameter. The larger diameter portion 2 I7 isdesigned to fit over the hollow shaft I96 of the rotor I97. Hydraulicfluid passage I86 extends through this hub portion 2I7.

16 The smaller diameter portion 2I9 is designed to fit over the shaft229 and to be secured thereto by any suitable means, such as the pin 22i. The shaft 229 is merely provided to synchronize the operation of thehubs 2I6 on both sides of the transmission.

The closure plate 22I secured in any suitable manner to the shellportion 295 of the housing acts to close the outer extremity of thiscasing. A manually operable handle 222 is provided with a suitable shaft223 extending axially through the closure plate 22L A planet gearcarrier 224 is provided with a hub 225, pin connected to the shaft 223,and this planet gear carrier is equipped with axes 226 and planet gears227. A sun gear 229 is secured to the closure plate 22! and is thereforeheld stationary with respect to the housing. The planet gears 22 7,illustrated in Figures 4 and 7 of the drawings, engage this sun gear 229and also engage the internal ring gear 239, forming a part of arotatable shell 23! of a diameter equal to that of the sleeve 295. Aspiral sprin 232, illustrated in Figures 4 and 6 of the drawings, isanchored at its inner end 233 to the planet gear carrier 224, while atits outer end 238, this spring 232 is connected to the rotor I97. Thisspring 232 forms a resilient connection between the rotatable shell 23Iand the rotor I97 for movement in one direction. A projection 234 on therotor I97 engages a cooperable projection 235 to positively rotate thetwo elements in unison when the handle 222 is operated in the oppositedirection.

The disk 2 I4 is provided with a paddle or vane 236, best illustrated inFigure 9 of the drawings, which substantially fills the space betweenthe sleeve 296, the shell 23I, and the outer housing 295. This vane 236extends from the disk M4 to the closure plate 22I so that when pressureis built up on one side of the vane due to the volume of oil within thehousing 295, rotation of the disk 2I4 will be caused. The hub 2H5 of thedisk 2I4 is provided with worm teeth 237 which are designed to engagethe gear 239 mounted on the end of the rotary control valve 299. Thusoperation of the control valve 249 is caused by rotation of the disk2I4, which in turn is rotated by oil pressure acting against the vane236 mounted thereupon. A spring 238 returns the disk M4 to startingposition when pressure against vane 236 is released.

The exhaust passage from the control device is provided through openings241 in the disk 259-, allowing the fluid to flow through the outletpassage 242, about the hub 2I6, and through the passage 243 around theshaft 229 leading into the oil reservoir within the casing I9. It willtherefore be obvious that oil may escape from the interior of the rotorshell 292 and accordingly from the interior of the rotary sleeve 23I,which abuts against the rotor l9'!, and which has no end wall to preventthe flow of fluid to the exhaust.

An aperture 244 is provided in the shell 23l through which hydraulicfluid may flow. The position of this aperture 249 is regulated by r0-tation of the control handle 222 for the purpose which will behereinafter set forth. The shell 23I is held in adjusted position by theball detent 245 which is urged into one of a series of angularly spacedindentations in the sleeve 233 by a spring 246.

Connected to the pressure passage I86 leading through the transmissioncasing to the reservoir on the interior thereof, we provide a hydraulicfluid passage 247. A butterfly valve 249 is mounted on a shaft 250extending through the passage 241, and an arm 25! is mounted on theshaft 250 externally of the housing fo use in rotating the shaft 256,and accordingly the butterfly valve 249. This arm 25! (see Fig, 14) isconnected to the accelerator 525 which controls the throttle arm 526 ofthe engine 527 which drives the transmission forming the subject matterof the present application. As a result the butterfly valve 249 isclosed at idling speeds of the motor and gradually opens to exhaust someof the oil being pumped by the pump I'll which is diverted back to thereservoir through the passage 24l', and the amount of oil thus by-passedincreases as the speed of the engine increases. This prevents thebuilding up of an excessive volume of oil within the control casing. Thepressure of the oil in chamber l 86 is regulated by the footaccelerator, so that the more the accelerator is open, the slower willbe rotation of the vane 236, and the slower will be the speed change inthe transmission. When valve 249 remains stationary, the speed changeincreases while the engine slows until a balance is reached.

Having now described the construction of the manually controlled meansused for controlling the engine, we will now explain the operation ofthis control. It will be understood that the purpose of the control isto regulate the position of the control valve 240, which controls thehydraulic fiuid pressure to the various clutches and brakes. The variouspassages from the control valve 240 will be later described in detail.

When the drive shaft starts to rotate, the hub 23 starts to revolveandthe worm gear teeth H4 act to drive the gear I on the shaft I16. Thepump HT is then set in motion pumping oil from within the casing in tothe pressure chamber I82 which acts to build up pressure in thispressure chamber, When the pressure reaches a predetermined maximum, thevalve l83 opens, allowing oil to flow into the passage I86. If theengine is rotated at an idling speed, sufiicient oil will by-pass pastthe butterfly valve l9! to prevent high pressure from being built upwithin the control. Oil passing through the passage I88 is communicatedthrough the opening are in the hollow shaft H96 and through the passage213i.

This oil may flow back through the openings 2 it and 2!! into theinterior of the shell 202, from which position it may escape through theopenings 241 in the disk 2l4, then passing through passages 242 and 243to the reservoir. Obviously in this neutral position or setting of thecontrol illustrated in Figure 9 the control valve 240 will i not beoperated.

Let us first consider that the manual control handle 222 is rotated in acounterclockwise direction until the handle indicates reverse. In suchan instance the projection 235 on the planet gear carrier 224 strikesthe projection 234 on the rotor 59?, rotating this rotor until thepassage 2ill communicates solely with the opening 250 in the shell 203.If the engine remains at idling speeds insufiicient pressure will bebuilt up to actuate the control. However, during this rotation of thecontrol handle 222 the shell 23! is rotated so that the opening 244 isin aslightly counterclockwise direction from the vane 236'. Therefore asthe speed of the engine is increased, hydraulic fluid under pressurewill be forced through the passage 2M and into the space between therotatable shells 206 and 23L and the outer casing 205 to the left of thepartition wall 201, as viewed in Figure 9 of the drawings. This pressuremay only escape through the aperture 244 in the shell 23L As thisopening is not un-'- covered in the starting position of the vane 236,the disk 214 is rotated by pressure againstthe vane 236 in acounterclockwise direction until the vane passes a portion of theopening 224, where upon the fluid pressure may escape to the'reser voirby passing through the interior of the shells 202 and 231 in the mannerwhich has been described. In other words, the fluid travels from passage26% and passage. 20! through aperture Ziilf Fluid passes between sleeves205 and 206 and through the passage 244 to the interior of the abuttingsleeves 23! and 286. Fluid passes through passages 24!, 242 and 243 tothe reservoir within the interior of the casing It]. This rotation ofthe disk 2M acts through the gear teeth 23? and the gear 239 to rotatethe valve 240 so as to apply the proper brakes and clutches to cause areverse motion of the drive shaft [5.

Let us now say for example, that it is desired to rotate the shaft l5 inthe lowest or first forward speed. The control handle 222 is rotated ina clockwise direction until first forward speed is indicated. Clockwiserotation of the control handle 222 acts through the planet gear systemdescribed to rotate the shell 23| in a clockwise direction. Tension isalso exerted on the spring 232 to rotate the rotor I97 into its otherextreme position. Accordingly the passage 21H is rotatedout ofcommunication with the opening 2H] in the sleeve 226 and intocomunication with the opening 2| I in this sleeve. If the engine istravele ling at idling speed, sufficient pressure will not be built upto operate the control, Upon in: creasin the speed of the engine,however, pressure is built up which issues through the passage 2%! andthrough the opening 2 to exert pressure against the vane 236, tending torotate this vane, and the disk 2M to which it i secured, in a clockwisedirection, as viewed in Figure 9.

In first forward speed the opening 244 in the. shell 23l is positionedin a clockwise direction from the vane 236. Thus in order to escapethrough this opening 245 to the exhaust the disk 254 is rotated in aclockwise direction until the vane 236 passes a portion of the opening244, allowing'the hydraulic fluid to exhaust. Therefore, as long assuflicient speed is maintained in the driving unit the drive shaft willbe rotated at firstor lowest speed. For each successive forward speed ofthe drive shaft from a lowest or first speed to seventh or superover-drive speed, the shell 23l is rotated a greater extent so that thevane 236 must rotate a greater distance to uncover this exhaust opening.Therefore, the speed at which the manual control handle is setdetermines the maximum speed ratio whichmay be attained for any settingof the control handle,

60 the vane 23S rotating the disk Zl l and the gear 231 on the hubthereof, to rotate the gear 239 and the control valve 2 2%. However, inorder to attain at the highest speed attainable, depending upon torqueand engine speed, it is only necessary to move the control handle to itsextreme position to indicate seventh speed or super over-drive po- Thenas the speed of the engine increases,

sition. the vane 23% will successively pass through each of the firstseven speeds until this vane finally reaches super over-drive position,whereupon ad- 19 ditional hydraulic fluid pumped will by-pass throughthe exhaust opening 244. Accordingly when set at any maximum speed ratiothe transmission-will automatically and successively pass through thevarious lower speed ratios until either the highest speed ratio isattained or until an intermediate speed ratio is attained, which is thegreatest which can be attained for the engine speed and torque relation.

As has been previously explained, the fluid passes through the valve I83and into the volume flow chamber I95. This chamber I95, as bestillustrated in Figure 9, is connected by a passage 252 which leads tothe end of the control valve 246. The control valve 246 is hollow,having a passageway 253 passing lengthwise through the same. The controlvalve 246 is provided with four valve portions 254, 255, 256, and 251,which are of larger diameter than the intermediate connecting portions259, 266, and 26 l. The larger diameter portions 254 through 251 fitclosely within the valve cylinder 262 which forms a part of the easing I6. Various passages are formed from the axial passage 253 to variousportions of the control mechanism in order to actuate these cooperatingparts.

A cylinder 263 extends parallel to and adjacent the control valvecylinder 262. As best illustrated in Figures 1, 3, and 9 of thedrawings, this control cylinder 263 is divided into three longitudinallyspaced separate cylinders. The first of these cylinders 264 isseparated. from the pressure chamber I82 by means of an end wall 265 andis separated from the second aligned cylinder 266 by a partition wall261. Similarly the cylinder 266 is separated from the next alignedcylinder 269 by the partition wall 216. The other end of the cylinder269 is provided with an end wall 21l.

A piston valve 212 is slidably positioned within the first cylinder 264and is normally held in one extreme position by means of a spring 213.In preferred form the piston valve 212 is hollow so as to require aminimum amount of weight. A boss 214 on the end of the piston valve 212engages the partition wall 261 in extreme position of the piston valve,thereby leaving a small space 215 between the end of the piston valve212 and the wall 261. The cylinder 266 is provided with a piston valve216 therein which is normally urged in one extreme position by a spring211. A boss 219 on the piston valve 216 spaces this valve from the wall261 in extreme position thereof. The cylinder 269 is provided with apiston valve 286 which is urged into one extreme position by the spring28!. A boss 282 on the piston valve 286 prevents this piston valve fromengaging against the wall 216 in extreme position.

A passage 283 connects the left hand end of the cylinder 264 to thecontrol valve cylinder 262 at a point opposite the enlarged portion 255of the control valve 246. The right hand end of the cylinder 264 isconnected by a passage 284 to an exhaust pressure passage 285 extendingparallel the axes of the cylinders 263 and 262. Thus the right hand endof the cylinder 263 always communicates with the exhaust passage whilethe left hand end of the cylinder may, upon proper operation of thecontrol valve 246, be subject to pressure.

The right hand end of the cylinder 266 is provided with a passage 286which communicates with the valve cylinder 262 opposite the enlargedportion 255 of the control valve 246. The space 281 encircling the smalldiameter portion'266 is connected to the exhaust passage 285 by thepassage 289. The left hand end of the cylinder 266 is connected by apassage 296 to the valve cylinder 262 opposite the enlarged diameterportion 256 of the control valve 246. Thus either end of the cylinder264 may be subject to pressure depending upon the position of thecontrol valve 246.

A passage 29! connects the right hand end of the cylinder 269 to thecontrol valve cylinder 262 opposite the enlarged diameter portion 256 ofthe valve 246. A similar passage 292 connects the left hand end of thecylinder 269 to the control valve cylinder. 262 opposite the enlargeddiameter portion 251 of the valve 246. The space 293 encircling thesmall diameter portion 26I of the control valve 246 is connected to theexhaust pressure passage 285 by a passage 294.

In Figures 2 and 3 of the drawings it will be noted that a passage 295extends through the shaft l5 axially thereof. This passage 295communicates with the passage 15 leading to the valve chamber of theslidable valve 13. The other end of the passage 295 communicates throughoutwardly extending passage 296 to a collector groove 291 whichcommunicates through the passage 299 with the cylinder 262 of thecontrol valve 246 0pposite the enlarged portion 251 thereof.

As best illustrated in Figure '13 of the drawings, the control valve 246is provided with a series of angularly spaced radially extendingopenings, that are in communication with the passage 253 through thecontrol valve. In other angular positions of the control valve, slotscommunicate with the spaces 281, 293, and 366 encircling the smalldiameter portions 266, 261, and 259 respectively of the valve 246. Thusat all times when the passages 284, 283, 286, 296, 29!, 292, and 299 arenot in commuication with the radially extending openings through thevalve, they are in communication with one of the spaces such as 281, 293or 366. These spaces respectively are connected to the exhaust passage285 through exhaust passages 289, 294, and 36 I.

The end 362 of the control valve 246 is also of reduced diameter and thespace 363 encircling the same communicates with the exhaust pressurepassage 285 through a passage 364. Thus all of the spaces encircling thesmall diameter portions of the valve 246 are connected to the exhaust.The arrangement of the pressure openings and exhaust openings in thevalve 246 is best illustrated in Figure 13 of the drawings. It will benoted that five pressure passages 365 are provided in the large diameterportion 251 of the valve 246 which, in various rotative positions ofthis valve, communicates with the passage 299 so as to permit pressureto enter the passage 299 which controls the position of the valve 13. Itwill also be noted that four slots 366 are pro- "vided in this largediameter portion 251 communicating with the space 363 encircling thesmall diameter end 362 of the valve 246, which is con,- nected to theexhaust passage 295. Similarly in the large diameter portion 251 of thevalve 246, three angularly spaced radially extending passages 361 areprovided which may communicate with the passage 292 at the left hand endof the cylinder 269. Likewise six slots 369 are provided in the largediameter portion 251 which communicates with the space 293 encirclingthe small diameter portion 26! of the valve 246. As a result in threerotative positions of the valve 361, pressure will be communicated tothe left hand end of the cylinder 269, while in all other rotativepositions of the valve the passage 292 will be in communication with theexhaust.

The large portion 256 of the valve 240 is provided with two angularlyspaced radially extending passages 3I0 which register with the passage29I in two different rotative positions of the valve 240. In seven otherrotative positions of the valve, slots 3H are provided which communicatewith the space 293 encircling the small diameter portion 26I of thevalve. Therefore,

-when the valve 249 is in two different rotative positions, pressurewill be communicated to the left hand end of the cylinder 269, whereasin all other rotative positions thereof, the passage 292 is communicatedwith the exhaust. V

The large diameter portion 256 of the valve 240 is likewise providedwith three spaced radially extending passages 3I2 communicating with thepressure passage 253 extending axially of the valve so that in threerotative positions of the valve, these passages 3I2 may communicate withthe passage 290 at the left hand end of the cylinder 266. Six slots 3I3are likewise provided inthe enlarged portion 256 so that when the valveis at any other rotative position the passage 290 will commnunicate withthe exhaust through the space 281.

7 The enlarged portion 255 of the valve 249 is provided with a pair ofradially extending openings 3I4 which in different rotative positions ofthe valve register with the passage 286. In all other rotative positionsof the valve, slots 3I5 in the enlarged portion 255 connect the passage286 to the space 281 which in turn is connected to the exhaust passage285.

The enlarged portion 255 of the valve 240 is also provided with threeradially extending passages 3I6 therethrough which connect the pressurepassage through the valve to the passage 283 leading to the left handend of the cylinder 263 in three different rotative positions of thevalve 249. In all other positions of the valve the passage 283 isconnected to the space 300, and therefore to the exhaust passage throughangularly spaced slots 3!! in the large diameter portion 255.

In summing up the description of the control valve 240 it will beobvious that the passage 299 is either in communication with pressure orwith exhaust through the passage 304. The passage 292 is likewise alwayseither in communication with pressure or exhaust by way of the passage399. Similarly the passage 29I is either subjected to pressure or toexhaust through the passage 294. The passage 290 ,is either subjected topressure or to exhaust through the passage 289. The passage 286 iseither subjected to pressure, or else is subjected to exhaust throughthe passage 289.

The passage 283 similarly is either subjected to pressure or to exhaustthrough the passage 30I.

When a reverse speed is desired, it is necessary that the valve 13remain closed so that the clutch R. remains engaged and so that thebrake D be engaged. Accordingly in reverse position pressure from theinterior of the control valve is communicatedonly through the passage 3|4 to the passage 286. Pressure in the passage 286 creates pressure onthe right hand side of the piston 216 which forces this piston to theleft, as viewed in Figures 1 and 3. Accordingly the piston valve 276closes the passages I29 of the brake unit D. At the same time the vanesH5 will be forced outwardly by the fluid pressure passing through thepassage 3I9 and the passage 329 and into the opening I43 for creatingpressure upon the inner end of the vanes I I5. At the same time thepressure leaving from the passage way 3I9 through II-8 forces theplungers I'2I to dis- 22 engage the vaneII5. This will create a pressure between the pistons 216 and the vanes H5 and retard the rotor I06to a standstill.

As noted in Figure 3 of the drawings, the right hand end of the cylinder266 is connected by a passage 3I9 and by the passage 320 to the rightend of the groove I40 in which the valve MI is located. This pressure istransmitted through the radially extending openin 32I, leading tothearea between the cam I09 and the inner surface I39 of the rotor I06, forthe purpose of creating a pressure on the inner ends of the vanes I I 5and at the same time the pressure from the passage 3I9 enters thepassage H8 to retract the plungers I2I, allowing outward movement of thevanes I I5 in the rotor I06. As the oil is thus forced to travel throughthe passageway I29, it is inter cepted by the piston 216. This willretard rotation of the rotor I06 as the oil pressure, is built upagainst the outward-ends of the vanes H5, thus locking the brake D.

,When a neutral speed is desired the control valve 240 may be rotated sothat all of the various passages are communicated with the exhaust, andnone of the clutches or brakes is engaged with the exception of thenormally engaged reversing clutch R. No movement is transmitted from thedrive shaft to the driven shaft when the control valve is in thisposition.

When a first forward speed is desired, the control valve 240 is turnedso that pressure is directed through the opening 3I6 to the passage 283,leading to the left hand out of the cylinder 264. This action tends toforce the piston 212 to the right, thereby closing the passages 3Z2noted in Figures 3 and 12. Before the piston 212 has closed the passages322, the vanes are released by the points 92 in the aperture 93 of thesaid vanes. Oil pressure passes through the passageway 96, groove 98,and passage 99 against the plunger 9I, compressing the spring 94. Thesprings 94 will then force the vanes outwardly into the space or pockets8I. Thusthe oil flow created by the vanes 85 will be intercepted by thepiston 212 which in turn will bring the rotor 83 to a standstill.Accordingly in the manner which has been described the vanes 85 will bestopped from rotation with respect to the casing section I6.

In order to provide a second forward speed, the brake A is released andthe brake B is engaged. The clutch R which is normally engaged remainsengaged in this speed. The brake B is engaged by oil pressure passingthrough openings M0 in the valve 240, which leads to the passage 2'9I atthe right end of the cylinder 269. Pressure at the right hand end of thecylinder 269 acts through the passages 323 and 324 to enter the grooveI6I in which the valve I62 is located. This pressure passes through theopening I64 to the space between the cam I49 and the rotor I52 to urgethe vanes I65 outwardly. Pressure also acts through the passages I I8adjacent the vanes I65 to retract the corresponding plungers I2I and torelease the vanes I65 for movement outwardly into engagement with thecam surface I66 of the casing section I9. Simultaneously the piston 280is forced to the left, closing the passage I6! and the sun gear 42 isheld from rotation, providing 2. second forwardspeed as has beenpreviously described.

In the remaining five speeds the clutch R is by communicating oil fromthepassage 253 in the valve 240, through the valve port 305, thepassages 299, 297, 296, and 295 to the passage communicating with thevalve chamber 12 of the valve 13. This pressure forces the valve 13 tothe left, opening a passage 'II, whereupon the oil under pressure isforced into the pockets 65 (see Figure 11) forming a part of the clutchB. This pressure forces th blades 69 inwardly, holding the sameretracted and thereby permitting free rotation of the rotor with respectto the enclosing casing flange I4.

In order to produce the third speed the clutch R is disengaged as hasbeen pointed out, the brake B remains engaged and clutch E is engaged.In Order to accomplish this result hydraulic liquid under pressureissues through the passage 3I2 in the control valve 246 which is at thistime in engagement with the opening 290 extending to the left hand endof the cylinder 265'. This pressure holds the piston 215 in the righthand position illustrated in the drawings and t the same time this fluidpressure passes through the openings I29 in a manner to force the bladesII5 inwardly. Simultaneously, pressure is transmitted through passagesI28 and H8, retracting the cooperable plungers I2! to release the vanesfor inward movement. Pressure is also transmitted through the passageU28 to the left end of the valve I4I, closing the by-pass passage I43 inthe cam I09. As a result the vanes I I5 engage the surface of the camI69, locking the rotor I from rotation with respect thereto.

As the cam I09 rotates in unison with the rotor I52 of the brake B, thelocking of the brake B therefore acts to lock the cam [09 from rotation.As the rotor I06 is locked with respect to the cam I69, this rotor isalso held from rotation. As a result both the sun gears 42 and 53 areheld from rotation.

To produce the fourth forward speed, the clutch E remains engaged andthe brake A is likewise engaged. The engagement of the brake A isaccomplished in the manner which has been described by rotating thevalve 240 until the opening 3 I 6 is in registry with the opening 283,forcing hydraulic fluid through the passage 233 in a manner to force thepiston 2'12 to the right end, simultaneously closing the passages 322 inthe brake A.

In order to produce a fifth forward speed, the clutch R remainsdisengaged, while clutches C and E are locked. Clutch 0 is locked byintroducing fluid under pressure through an opening 301 which is incommunication with the passage 292 to the left hand end of the cylinder259. This action holds the piston 286 in its normal right hand positionand forces fluid under pressure through the passage I 61 to force thevanes I inwardly. Pressure is also transmitted through passage 268 tothe left end of the valve I62, which moves to close the by-pass passagesthrough the cam I49. Pressure is also transmitted through passages 268and H8 to retract the cooperable plungers I2I to release the vanes I65for inward movement. The vanes I65 lock the rotor I52 with respect tothe cam I29 so that the rotor and cam rotate in unison. However, as thecam I49 is secured to the driven shaft the rotor I52 is locked forrotation therewith also. The manner in which the clutch E is locked hasbeen described in detail in connection with the explanation of the thirdforward speed.

In the sixth forward speed the clutch R remains released and clutch Cand brake A are engaged in 24 the manner described. For a seventhforward speed clutch R still remains disengaged and clutch C and brake Dare engaged in the manner which has been described.

In the operation of the various clutches and brakes, the arrangement issuch that the vanes engage the proper cam surface before the by-passvalve closing the by-pass between rotor pockets is closed. For examplein brake A, the spring H3 is stronger than the spring urging the plunger9i into locking position. As a result the plunger 9I disengages thevanes for outward movement before the piston 212 moves to the right asviewed in Figure 3 to close the by-pass passage between the pockets 322.This action retards and cushions the stopping of the rotor 83 relativeto its casing 15; v A further cushion is provided by the air chamberwithin the rotor 83.

The brakes B and D operate similarly to the brake A with the exceptionthat hydraulic pressure rather than spring pressure acts to urge thevanes outwardly. Pressure introduced at the right end of cylinder 259first passes through passages 323 and H8 to disengage the correspondingplunger I H from the vane to release the vane for outward movement. Thepressure also simultaneously passes through the passages 323, 324, valvechamber WI and passages I64 to exert outward pressure on the vanes I65.Subsequently, spring 28I is contracted and piston 288 moves to the left,closing passages I67. The stopping of the rotor I52 is thus cushionedand is further cushioned by the air chambers I32.

The brake D operates in an identical manner with brake B. The plungersI2I holding vanes H5 from outward movement are first retracted bypressure through passages EIS and H8. Simultaneously, pressure passingthrough passages 3I9 and 32B, valve chamber I40 and passages I43 urgethe vanes outwardly. The pistons 276 then move to the left as viewed inFigure 3, gradually closing bypass passages I29 and thus cushioning thestopping of the rotor I66. The air chambers I32 Within the rotor furthercushion this stopping. The clutches C and E also operate similarly.Pressure from the left end of cylinder 269 acts through passages 268 andM5 to retract the plunger I2! to release the vane I65 for inwardmovement. Simultaneously pressure acts through passages I61 to urge theblades inwardly. Pressure subsequently acts through passage 238 togradually close the valve I62, to cushion the locking of the rotor I52.The air chamber I46 also assists this action.

Pressure in the left end of cylinder 266 is transmitted through passagesI28 and H8 to retract the cooperable plunger I2I holding the vanes I I5from inward movement. Simultaneously pressure through passages I29 actsto urge the vanes inwardly. Subsequently, pressure through passage E23urges thevalve MI to the right, gradually closing this valve. Thestopping of the rotor I56 is further cushioned by the air chamber 246within the rotor I65.

Figure 10 illustrates diagrammatic-ally the inner surface of each of thecylinders 254, 266, or 259. The surface of each of these cylinders isgrooved with grooves 325, shaped substantially as illustrated so as toequalize pressure on opposite sides of the pistons within the cylindersand therefore to prevent these pistons from binding against the wall andbeing difficult to slide. These grooves are of small size, and thus donot leak an appreciable amount of fluid.

In accordance with the patent statutes, we have.

described the principles of construction and operation of our hydraulictransmission control, and while we have endeavored to set forth the bestembodiments thereof, we desire to have it understood that obviouschanges may be made within the scope of the following claims Withoutdeparting from the spirit of our invention.

What is claimed is:

1. The combination of a variable ratio transmission of the typeincluding a driving shaft, a driven shaft, a control valve movablethrough a series of positions, and change speed gears between saidshafts, said gears being rendered effective by the control valve in thesuccessive positions thereof to establish a series of different drivingratios between said shafts; a reservoir for hydraulic liquid; ahydraulic pump 0perated at a speed proportional to that of the drivingshaft and adapted to withdraw liquid from said reservoir and deliver itunder pressure; means providing a constantly open vent proportioned todissipate the pressure developed by said pump at low speed; a movableabutment subjec to pressures developed by said pump and connected toshift said control valve toward its high gear ratio setting; yieldingmeans arranged to offer a progressively increasing resistance to motionof said abutment as the latter moves in the direction to establish thehigh gear ratio setting of the control valve; a member movable along thepath of said abutment and having a relief port adapted to beover-traveled by the abutment and serving when over-traveled to venthydraulic liquid to said reservoir and thus limit the motion of theabutment in response to pressure developed by the pump; and manuallyoperable means for adjusting the position of the last named member.

2. The combination defined in claim 1 in Which the area of theconstantly open vent is manually adjustable whereby the speed at whichthe abutment becomes effective to shift the valve may be adjusted.

3. The combination of an engine having a throttle by which the speedoperation of the engine is controlled; a variable ratio transmission ofthe type including a driving shaft driven by said engine, a drivenshaft, a control valve movable through a series of positions, and changespeed gears between said shaft, said gears being rendered effective bythe control valve in the successive positions thereof to establish aseries of different driving ratios between said shafts; a reservoir forhydraulic liquid; a hydraulic pump operated at a speed proportional toengine speed and adapted to withdraw liquid from said reservoir anddeliver it under pressure; means providing a constantly open ventproportional to dissipate the pressure developed by said pump at lowengine speeds; a movable abutment subject to pressures developed by saidpump and connected to shift said control valve toward its high gearratio setting; yielding means arranged to offer a progressivelyincreasingresistance to motion of said abutment as the latter moves inthe direction to establish the high gear ratio setting of the controlvalve; a member movable along the path of said abutment and having arelief port adapted to be over-traveled by the abutment and serving whenover-traveled to vent hydraulic liquid to said reservoir and thus limitthe motion of the abutment in response to pressure developed by thepump; manually operable means for adjusting the position of thelastnamed member; an adjustable liquid throttling valve for venting to thereservoir liquid delivered by the pump; and a controller for operatingthe engine throttle and the liquid throttling valve conjointly and soarranged that the two are moved in opening directions in a definiterelation to each other.

4.The combination defined in claim 3 in which the area of the constantlyopen vent is manually adjustable whereby the speed at which the abutmentbecomes effective to shift the valve may be adjusted.

5. The combination defined in claim 3 in which the abutment is a vanearranged to swing in a circular are about an axis and the adjustablemember which carries the relief port is a concentric sleeve.

6. The combination defined in claim 3 in which the engine is an internalcombustion engine, the constantly open vent is proportioned to dissipatethe pressure developed by the pump at the'idling speed of the engine,and the control valve establishes a neutral condition of thetransmission when the abutment is relieved of pressure.

ALBERT L. JOHNSON. SELMER vA. KRAFT.

REFERENCES GITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date Re, 21,844 Vetter June 24, 1941907,711 Anthony Dec. 29, 1908 1,199,640 Vincent Sept. 26, 1916 1,609,782Small et al Dec. 7, 1926 1,818,910 Sanine Aug. 11, 1931 1,910,180Poncelet May 23, 1933 1,979,830 Griserti Nov. 6, 1934 2,019,146Livermore Oct. 29, 1935 2,075,944 Hughes Apr. 6, 1937 2,161,008 BonnJune 6, 1939 2,223,716 Bojesen Dec. 3, 1940

